Aprilaire installation instructions?

[beelzerob]

They're installing the HVAC and thermostat soon for our heatpump system, and my plan is to eventually replace it with an aprilaire. All I had heard from the forums here was to make sure they include a "C" wire...well, that didn't exactly make things clear to him, so I had hoped to simply get a copy of the installation procedure for removing an existing thermostat and replacing it with an aprilaire (presumably 8870), but I can't find one on their website.

Does anyone know where I can find one, or at a minimum....what do I tell the HVAC guy that he has to do with his regular thermostat install, such that I'll be good to go for installing my own thermostat later (whether aprilaire or any other rs232 controlled one). I'll of course be running cat5 to the location, but I mean on his side of things.

 

[Steve]

Here is the 8870 install guide. I think you just need to have a Cat5 from the stat to the Air Handler/Heat Pump, but I'm not 100% sure. I think most regular stats just use 4 wires and you'll need more than that, hence the Cat5. So I think if you just have them put a Cat5 instead of their normal stat wiring, or double it up, so you have 2 of them (for 8 or 10 wires) then you should be good.

 

[beelzerob]

Well, I was going to run my own cat5 to the thermostat location for control. I was more concerned about whatever wires are involved going from their stock thermostat to the heatpump unit. I'd been told to make sure they put in a "C" wire....the HVAC guy just assumed that was common, and seemed to indicate that of COURSE there'd be a common there....

Edit: Thanks for the instructions, Steve....looks like page 20 should tell him what wires this thing will need eventually. As long as the thermostat he's installing uses those same wires, then no problem.

 

[Steve]

Well I have not automated my stat yet since I'm having trouble replacing a nice Honeywell touch stat a few years ago, but iirc I only have a 4 wire bundle to my stat and none are common. I think it was actually quite common (pun intended) to run only 2 pair. And I think this was an issue with the HAI stat requiring a common line and some people don't have one. Things may be different now - I'm sure somebody much more knowledgeable about HVAC will jump in. But bottom line I think is if you have 8 or so stat wires there you should be ok. Of course with the 8870 you also have to deal with the 8811? converter.

 

[magrann]

I am not certain about a heatpump set-up. But what I would say as long as you have enough wires you should be ok. So perhaps, the cat5e, you may want to run 2 for future purposes (temp sensor, etc..) and then for the unit itself I think an 6 or 8 conductor wire.

 

[beelzerob]

I am not certain about a heatpump set-up. But what I would say as long as you have enough wires you should be ok. So perhaps, the cat5e, you may want to run 2 for future purposes (temp sensor, etc..) and then for the unit itself I think an 6 or 8 conductor wire.

Well, that's why I posted....I don't know what "enough wires" is!

I mean exclusive of control wires (rs232)...I mean just the wires that go from the thermostat to the actual furnace/fan/heatpump. Basically, when I remove the stock installed thermostat, what wires (other than cat5 which I'll run) will I need to be able to see in order to install the aprilaire in its place.

I think the installation manual should be enough for him to go on.

 

[bingl]

Confusing, eh? Don't feel like the Lone Ranger. I was just there myself.

Like Steve said...4 wires are common and none are "C". I can understand how a knowledgeable HVAC guy may think "of course" the common wire will be there. Mine, had no common wire showing AND doing the jumpers is not clear.

Bottomline, with a diagram (courtesy of Steve) AND a six wire T-stat bundle. You are not missing wire installs. Connecting correctly later on will be another project in itself. (see other threads on this)

Good luck. I really like my 8870's.